Multiple fluid delivery system with liquid and gas purging means



March 19, 1968 w. .1 KORCHAK 3,373,762

MULTIPLE FLUID DELIVERY SYSTEM WITH LIQUID v AND GAS PURGING MEANS FiledOct. 15, 1965 2 Sheets-Sheet 1 SUPPLY AIR SUPPL Y INVENTOR.

M17220? J Aorckak I HIS ATTORNEY TH/NNER March 19, 1968 w. J. KORCHAK 3,

MULTIPLE FLUID DELIVERY SYSTEM WITH LIQUID AND GAS PURGING MEANS v FiledOct. 15, 1965 2 Sheets-Sheet 2 y l 71 J, 70 6% 7 9 a? x .w l I aINVENTOR.

ZI/fHfd)?! (I /1 orchak ms arromvzy United States Patent 3,373,762MULTELE FLUID DELIVERY SYSTEM WITH LIQUID AND GAS PURGING MEANS WilliamJ. Korchak, Arlington, Tex., assignor to General Motors Corporation,Detroit, Mich., a corporation of Delaware Filed Oct. 15, 1965, Ser. No.496,602 Claims. (Cl. 137240) This invention pertains to a multi-colorpaint spray system and more particularly to an arrangement wherein anyone of many colorscan be selected in any desired sequence.

In the merchandising of a wide variety of products, the availability ofa wide selection of colors is important. The need for selection ofcolors makes necessary frequent changes of paint colors and othersurface coatings in manufacturing operations requiring rapid effectivecleaning of the common paint supply lines and the connections betweeneach change of paint color to prevent contamination of the differentpaint colors supplied.

It is an object of this invention to provide a multiple fiuid deliverysystem which can effectively and rapidly purge between each change offluids with a minimum of waste and a minimum of contamination.

It is another object of this invention to provide 'a multiple fluiddelivery system in which the portions of the system common to all of thefluids have a minimum of volume arranged in a short narrow straightpassage pro viding a straight-through flow of purging fluids from end toend.

It is another object of this invention to provide a multiple fluiddelivery system in which the individual valve outlets are concentratedabout a short passage which is provided with a straight through flushingarrangement.

These and other objects are attained in the form shown in the drawingsin which a plurality of air operated needle valves are arranged radiallyin a staggered arrangement about a centrally located passage into whichthe paint flow-s after passing through the needle valve. The paint flowsfrom this passage directly to the spray gun. In between each change ofpaint, purging fluids are introduced at the end of the centrally locatedpassage opposite the end which is connected to the spray gun forstraight through effective flushing.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein preferred embodiments of the present invention areclearly shown.

In the drawings:

FIGURE 1 is a diagrammatic view of a multi-color paint delivery systemincluding a portion in section taken along the line 11 of FIGURE 2;

FIGURE 2 is a side view of the multiple color selector shown in sectionin FIGURE 1; and

FIGURE 3 is an enlarged fragmentary sectional vie-w taken along the line33 of FIGURE 1 with the needle valves shown in elevation.

Referring now more particularly to FIGURE 1, there is shown a paintsystem including four paint supply tanks 20, 22, 24, and 26 which arerepresentative of the 18 supply tanks, each containing a difierent colorpaint or surface coating material. These 18 tanks are normally used withthe 18 needle valve arrangement shown more particularly on the drawing.Each paint supply tank is connected to a supply conduit 28 connectingwith a delivery pump 30 which delivers paint to the discharge conduit 32connecting with an air operated valve 34 from which the paint isreturned through a restricted outlet and a return conduit 36 to thepaint supply tank. The valves 34 'ice and the pumps 30 connected to eachpaint tank 20-26 for example, are identical as are the systems for allthe 18 various color paints which supply paint to the various needlevalves. T'hese valves 34 include a side air pressure supply connection76 arranged to open the valve 34 for the delivery of paint through thedelivery conduit 40 to the valve chamber 42 containing the needle valve44 which cooperates with the needle valve seat 46 in the stainless steelsleeve 48 provided in the hub 50 of the wheel-shaped member 52. Theseats 46, the valve chambers 42. and the valves 44 are arranged radiallyabout the axis of the central bore 54 of the sleeve 48. The valve 42 isprovided with a packing gland 56 through which extends the valve stem 58connecting with a double acting piston 60 in a double ended air cylinder62.

A compressed air supply 64 delivers air through the supply conduit 66through a two-way solenoid operated paint selector control valve 68either through the valve closing conduit 70 to the outer end of thecylinder 62 or through the valve opening conduit 72 connecting with theside of the cylinder 62. The conduit not connected to the compressed airsupply may be connected to the air exhaust connection 92. The conduit'70 is also connected through the branch conduit 74 wit-h the outer endof the valve 34 to keep the valve 34 closed to prevent delivery of paintthrough the conduit 40. The conduit 72 has a branch conduit 76connecting with the side of the valve 34 to open the valve 34 to allowdelivery of the selected paint from the circulating paint system 20, 28,30, 32, 36 to the delivery pipe 40 for flow through the valve chamber 42and the valve seat 46 which opens and delivers into the central bore 54for delivery through the bore 54 and the conduits "78 and 86 to thepaint spray gun 82 which may be provided with a solenoid control valve83. The valve 34 preferably has a double acting piston and a doubleended air cylinder similar to the piston and cylinder 60 and 62 and hasa valve stem and an outlet valve for closing its connection to thedelivery pipe 40. The use of the two valves 34 and 44 is designed toprovide double assurance for the prevention of any leakage into thepassage 54. Any such leakage could cause contamination of the paint.

As is better shown in FIGURE 3, the central bore 54 is relatively smalland the individual valve seats 46 extend to the center bore with theends of the needle valves 44 closing the valve seats 46 all the way tothe junction of the seats with the bore 54. The tips of the needlevalves as shown in FIGURE 3 actually project into the bore 54. The seats46, the valves 44 and the valve chambers 42 are arranged radially in twoseries of nine each, about the axis of the bore 54. Each series isstaggered with the valves 44 in one series being arranged in a group offive, 72 apart and a second group of four also with a 72 spacing andstaggered relative to the group of five and offset axially as indicatedby the valve chamber 42 in FIGURE 1. A key 84 is provided for assuringexact orientation 'between the sleeve 48 and the hub 50 located 72 fromthe four needle valves and seats in the second group. However, ifdesired, some other system of keying or orientation might be usedbetween the sleeve 48 and the hub 50 thereby making room for one or moreadidtional valves, valve chambers, seats and paint supply systems ineach series.

The eighteen cylinders 62 each have an inner boss 86 threaded into anintegral transverse flange 88 projecting on opposite sides of anintegral radial web 90 which is formed integral with the hub 50. Oneseries of nine pistons 60, cylinder 62, valve stems 58, needle valves44, valveicharnbers 42 and valve seats 46, is arranged on one side ofthe web 90 and the second series of nine which is identical to the firstseries is arranged on the opposite side of the web 90. The selection ofcolors is made by the selective energization of any one of the paintselector solenoid valves 68.

According to my invention, when it is desired to change colors, thesolenoid valve 68 of the paint being currently supplied is deenergizedto cause it to discontinue the supply of air pressure through theconduits 72 and 76 to the side of the air cylinders 62 and the side ofthe valve 34 and to connect these conduits to the air exhaust connection92, while air under pressure is supplied through the conduit 70 to theend of the cylinder 62 and through the conduit 74 to the end of thevalve 34 to close the valves 34 and 44 to stop the supply of thatparticular color paint to the bore 54.

Immediately the solenoid valve 94 is energized to provide a supply ofcompressed air from the compressed air supply 64 through the supplyconduit 96, the branch conduit 98 through the valve 94 and the conduit121 to the side of the valve 123 which will then open. This provides fora flow of paint thinner or other suitable solvent from the thinnersupply source 125 through the thinner supply conduit 127 and the openvalve 123 into the common purge conduit 129 which connects through thecheck valve 131 with the end of the bore 54 which is opposite the end towhich is connected the delivery conduit 78. After there is sufiicientflow through the bore 54 and conduits 78 and 80 and the spray gun 82 toclear all of the paint therefrom, the valve 94 is deenergized to connectthe conduit 121 to the air exhaust 133 while the branch conduit 98 isconnected to the conduit 135 connecting with the outer end of the valve123 to close the valve 123.

The thinner is expelled from these parts by a blast of air initiated bythe energization of the solenoid valve 137 which connects the branchconduit 139 with the conduit 141 connecting with the side of the airvalve 143. This opens the air valve 143 to allow a blast of highpressure air to flow from the conduit 96 through the branch conduit 145,the common purge conduit 129, the check valve 131, the bore 54, theconduits 78 and 80 and the spray gun 82 which has its solenoid valveenergized to open to expel all of the thinner from these enumeratedparts, Thereafter, the solenoid valve 137 is deenergized to connect theconduit 141 to the exhaust 147 and to connect the branch conduit 139 tothe conduit 149 connecting with the end of the valve 143 to close thisvalve 143.

After this, any other paint selector solenoid valve 68 may be energizedto open another needle valve 44 to supply another color paint to thebore 54, the conduits 78 and 80 and the spray gun 82. The discharge fromthe spray gun 82 is controlled by the energization and deenergization toopen and close the valve 83. With this arrangement the supply of thepaint and thinner which is lost during each change of paint colors isminimized because of the small volume of the bore 54, the completeclosing of the needle valve seats to their very entrance into the bore.The arrangement of the purging connection and the paint delivery conduitconnection 78 at the opposite ends of the short straight bore 54 insuresthorough and rapid removal of the paint and thinner between each colorchange. The number of color paints provided may be increased by spacingthe valves and valve chambers closer and by providing additional seriesof valves and valve chambers in the hub 50 and sleeve 48.

While the embodiments of the present invention as herein disclosed,constitute preferred forms, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. A multiple fluid delivery system including tubular means having anaxially extending passage and a plurality of transversely positionedpassages extending to said axial passage, each provided with a valveseat, each of said transverse passages being provided with a valvepositioned transversely relative to said tubular means cooperating withthe valve seat therein, means for delivering different fluids to saidtransverse passages for delivery under the control of the valvesprovided therein to said axially extending passage, a fluid dischargemeans connected to one end of said axially extending passage and purgingmeans connected to the opposite end of said axially extending passagefor delivering a purging fluid to said axially extending passage forconduction therethrough.

2. A fluid delivery system as defined in claim 1 in which said purgingmeans comprises means for delivering a liquid solvent and means fordelivering a gas.

3. A fluid delivery system as defined in claim 1 in which each of saidvalves are connected to a double acting fluid motor.

4. A fluid delivery system as defined in claim 1 in which saidtransverse passages and valves are arranged in two series extendinggene-rally circumferentially about the axis of the tubular means.

5. A fluid delivery system as defined in claim 1 in which saidtransverse passages and valves are arranged in a staggeredcircumferential arrangement around the axis of said tubular means.

References Cited UNITED STATES PATENTS.

2,178,559 11/1939 Cohen 137-240 X 2,257,004 9/1941 Fleming 137240 X3,180,350 4/1965 Rill 137-607 X 3,219,273 11/1965 Killen 137-240 X3,240,225 3/1966 Barrows 137240 CLARENCE R. GORDON, Primary Examiner.

Disclaimer 3,373,762.William J. Ko'rchak, Arlington Tex. MULTIPLE FLUIDDE- LIVERY SYSTEM WITH LfQUIl) AND GAS PURGIN G MEANS. Patent dated Mar.19, 1968. Disclaimer filed June 26, 1972, by the assignee, GeneralMotors Gorpomtion. Hereby enters this disclaimer to claims 1, 2 and 3 ofsaid pabent'.

[Ofi'icz'al Gazette February 20, 1.973.]

1. A MULTIPLE FLUID DELIVERY SYSTEM INCLUDING TUBULAR MEANS HAVING ANAXIALLY EXTENDING PASSAGE AND A PLURALITY OF TRANSVERSELY POSITIONEDPASSAGES EXTENDING TO SAID AXIAL PASSAGE, EACH PROVIDED WITH A VALVESEAT, EACH OF SAID TRANSVERSE PASSAGES BEING PROVIDED WITH A VALVEPOSITIONED TRANSVERSELY RELATIVE TO SAID TUBULAR MEANS COOPERATING WITHTHE VALVE SEAT THEREIN, MEANS FOR DELIVERING DIFFERENT FLUIDS TO SAIDTRANSVERSE PASSAGES FOR DELIVERY UNDER THE CONTROL OF THE VALVESPROVIDED THEREIN TO SAID AXIALLY EXTENDING PASSAGE, A FLUID DISCHARGEMEANS CONNECTED TO ONE END OF SAID AXIALLY EXTENDING PASSAGE AND PURGINGMEANS CONNECTED TO THE OPPOSITE END OF SAID AXIALLY EXTENDING PASSAGEFOR DELIVERING A PURGING FLUID TO SAID AXIALLY EXTENDING PASSAGE FORCONDUCTION THERETHROUGH.